OF THE FUNGI. 115 



CHAPTEE XII. 



OF THE' FUNGI. 



As the Alg.e require water in larger or smaller quantities 

 for their support, so the Fungi demand for their perfect 

 deve]opment the decaying remains of other organisms. 

 Wherever rottenness and corruption are present, there are 

 we sure to meet with a rich Fungal vegetation. Let a 

 plant for instance be sickly, it is seized upon immediately 

 by a host of parasites belonging to this class ; their cotton- 

 like mycelium penetrating its cellular tissue, disorganising 

 its structure, and extracting nourishment from its infected 

 juices. Wet wood, fallen leaves, animal excretions, all 

 afford a nidus for these scavengers of nature, who only 

 spring from the earth itself when the latter is rich in 

 humus, or, in other words, in decayed vegetable matter. 

 For a like reason they are to be found in abundance on 

 damp tree stems and in mines and cellars, where fragments 

 of rotten wood supply the conditions necessary to their 

 existence. It must not however be imagined, that, because 

 they are found in deep mines or in cellars, into which the 

 rays of the sun never find their way, Fungi are less 

 dependent for their perfect development on the action 

 of light and air, than the more highly organised members 

 of the vegetable kingdom. The fact is, that they exist 

 in these localities only in a certain condition, as byssoid 

 products or mycelium ; they never come to perfection. 

 It is a matter of grave doubt to this day, what is the perfect 

 form of the well-known Ehacodium cellare. 



There is in truth scarcely a single object in the whole 

 realm of nature which is not liable to the attacks of these 

 minute enemies. The timber of our houses, as many a 



I 2 



